We present the results of a series of Chandra observations
of globular cluster (GC) X-ray sources in M31. Among some 20
GC X-ray sources detected in our M31 observations, 2-3 of
them show super-Eddington luminosity (> 1038 erg
s-1). It is an interesting fact that the highest X-ray
luminosities achieved by Galactic GCs are only several times
1037 erg s-1, and that none are black hole
candidates. There are several possible explanations for such
a large luminosity: 1) there are multiple sources; 2) the
source is a black hole; 3) the flux is beamed. In addition,
metallicity can account for higher luminosities than the
standard Eddington limit. Some of the M31 GC X-ray sources
are also variables and show transient behavior. By combining
all the available archival data, we compare the properties
of these sources to those Galactic GC X-ray sources.

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akong@cfa.harvard.edu